“I could make a lot of jokes about what kind of job this is, but I won’t,” said Scott Reynolds, who runs the company with his wife, Karen. “They alert us to the presence of human-specific bacteria, E. coli, poop, whatever you want to call it.”

“Everyone seems to smile and immediately become a little bit happier,” says Barbara Goldberg, CEO of O’Connell & Goldberg, a public relations company based in Hollywood, Florida. Her bulldog, Rosie, is a frequent visitor.

Aurora Animal Care Manager Jenee Shipman said the city has not seen an increase in dogs and cats coming from large-scale breeders, but that sometimes it is hard to tell where animals come from because the Aurora Animal Shelter accepts any animal a visitor brings in and must rely on them as a trusted source

“Dog brains care about both what we say and how we say it,” said lead researcher Attila Andics, a neuroscientist at Eotvos Lorand University in Budapest. “Praise can work as a reward only if both word meaning and intonation match.”